As usual, roster activity around the minors has increased greatly as the MiLB regular season approaches its final weeks. A slew of notable prospects are on the move to new clubs at new levels, and I’ve been doing my best to keep y’all informed in my weekly Minor Accomplishments posts. Well this past Sunday, I neglected to mention that Trayce Thompson, a big swinging outfielder in the White Sox system, was bumped up to Double-A Birmingham in the Southern League. The reports on Thompson have always been consistent: extremely toolsy, but extremely raw. With a huge swing from the right side he generates big time bat speed, translating to plus-plus power. Thompson hit 24 homers and posted an ISO of .216 last year at Low-A, and the power didn’t cease this year when the Sox moved him to High-A: 55 XBH (22 HR) in 510 PA, .232 ISO.

A tall, lean outfielder, Thompson’s power potential only stands to improve as he fills out his athletic frame. He certainly projects to hit 30+ homers annually at the big league level, but that projection comes with a big caveat: Thompson whiffs a ton. That big swing I was telling you about… the one that crushes pitches outta the park… well that big swing doesn’t always make contact. Thompson’s K-rate at High-A was a healthy 28.2%, down only a tick from the 28.8% mark he posted in 2011 at Low-A. With an approach so prone to swings and misses, Thompson could be in for a rough go versus the advanced arms he’ll face at Double-A. All the excitement over his raw power will be forgotten quickly if he fails to adjust. The early results from Birmingham are in, however, and they’re good: 4 XBH (2 HR) in his first 24 PA. Granted the sample is small — he’s also struck out seven times during that span — but the power persists. There’s plenty of reason to believe that Thompson will never shed the whiffs, but if he can continue to post impressive power figures, he’ll arrive at US Cellular Field before long, perhaps as soon as September 2013.

Considered the top high school pitcher among this year’s draft class, Lucas Giolito was also considered an enormous risk. An elbow injury in March ended his amateur career and damaged his draft stock, but the setback didn’t deter Giolito and his representation from seeking a big time bonus. Once considered a potential No. 1 overall pick, the teenage flamethrower slipped to 16th, where the Washington Nationals decided his upside was too big to pass over. Giolito held out ’til the deadline, but ultimately signed with the Nats for a bonus worth about $3 million. Optimistic folks were thinking that this signing was quite the steal — Giolito stands 6-6, 230, and works his fastball in the mid-upper-90s, touching 100 at times. His secondary stuff projected as plus offerings too. Suffice to say, it wasn’t very hard to picture this kid as a future ace.

Well, Giolito made his pro debut on August 14th in the rookie level Gulf Coast League. He tossed two innings, surrendered a couple hits, and struck out one. He also re-injured his elbow. The extent of the injury is not yet clear. But if you like to speculate (and I do), it seems plausible that the 18-year-old will need surgery to repair the elbow. It was ligament damage that ended his high school career — some tearing, but nothing that needed surgery. In light of this recent re-injury of the elbow, I don’t think it’s too far a leap to assume that the ligament will require surgery this time. Of course, we’ll have to wait to see what the Nationals have to say about situation, but there’s ample reason to believe that Giolito’s development will be put on hold for a year.